Electric lamp socket



Dec. 8, 1942. J MCCARTHY 2,304,108

ELECTRIC LAMP SOCKET Filed July 19, 1940 MI tlllllllllwllllllll l l \lllllllllll /9 V I 1 *1 2/ n m1"\m.=.

HENRY J. M CARTHY INVENTOR.

A'r-roclvs Y Patented Dec. 8, 1942 v UNITED. .s ArE ELECTRIC LAMP soCKE'r Henry J. McCarthy,

Sylvania Electric of Massachusetts Application July 19, 1940',

' zciaims; (Cl. 173- 328) My invention relate to a socket for electric. lamps and more particularly to a socket for electric gaseous discharge lamps of the tubular type.

An object of my invention is to provide a socket so constructed as to permit a quick and-easy insertion of the lamp therein. r

.Another object is to provide a socket. so .constructedas to create a positivelocking position when the lamps are inserted therein.

A further object is to provide'a socket so designed in its structure that it will obviate any. possibility of base pins from being accidentally inserted or withdrawn improperly and thereby placing a strain on the pins the base, and-the socket itself. 1

Further objects and advantages will be apparent from the accompanying specification and drawing inwhich: w

Figure l is a rear elevational view of the base member; i

Figure 2 is a front elevational view of the com-. pletesocket; v i a Figure 3 is a bottom view of the base member;

Figure 4 is a top view of the base member;

Figure 5 is a side perspective view of the sockets with a lamp therein;

Figure 6 is a front perspective view of the cover plate;

Figure 7 isa schematic diagram of thelamp socket showing the positions which the base pins assume when moving in or out of the locking position in the socket;

Figure '8 is a schematic diagram of the lamp socket showing the positions which the, base pins assume when they are in the lockingposition in the socket.

Similar reference characters refer to similar parts throughout the several views of the drawing and in the specification which follows.

The socket, according to my invention, comprises two pieces of insulating material, one of which is a cover plate, I, and the other a base member 2. The insulting material is dye cast in a manner as to provide a base member of a contour substantially as shown in Figure 1.

The studs 3 and 4 in the base member 2 are so located as to serve as a restraining means on the flexing of the spring contact fingers 5 and 6. The stud 'l in the base member 2 is located between the contact fingers 5 and 6 and serves as a means of preventing these contact members from touching each other. It also serves as a means through which the cover plate i may be attached to the base member 2.

The upper section of the inner face of the base 55 .ment of the lamp,

' pressureto be exerted at the pin fingers 5 willflex and the pin 12 will movestillfurther down along the side f the triangular When this pressure is exerted at-the,

the pin l3' will be. relieved .slightly and the pins will tend to center them; selves in their locking positionsas shown in Figure 8. The locking positions are created by pin'l2, pressure at Danvers; Mass, assigno'r to Products Inc, a corporation Serial No. 346,357 7 member is cutout to isosceles triangle except that the equal sides 9 and I0 do not meet to formythe apex anglebut flare out to provide the flared slot ll through which the base pins may pass .when they 2 are in alignment with the slot; r

When a lamp is to be inserted in the la mp socket, the base pins are brought into alignment,

with the flared slot II. By a downward movethe triangular cut-out8. -By rotating the lamp, slightly in a clockwise or counter-clockwise man-' ner, thepin first to enter the cut-out 8'will slide ID of the cut-out.'-.-As-

along either side 9 or side suming that the lamp is rotated slightlyi'nma counter-clockwise manner; the pin 13 will slide,

along side Ill until it'touches the spring contact finger 6. Byapplyin aslight pressure on the lampat this point, the contact finger will flex and the pin l3 will assume a position similar to; When this point has:-

that shown in Figure "7.

been reached the pin l2 has passed through the flared slot ll. andassumed aposition along-the side 9 of the triangular cut-out 8-similar. to. that shown in Figure 7.

. By rotating thelamp counter-clockwise l2 will slide-down the side 9 until. 5. B ga in manner the pin it touches the spring contact finger l2, .the contact cut-out,

their locking positions, it may be clearly seen that the only way in which the pins could be removed is by rotation of the lamp. Both pins could not become loose and drop out of their locking positions at the same time because of the angular disposition of the sides 9 and ID to which I they are tangent. One of these pins could not become loose and drop out of its locking position because for this to happen it would be necesprovide the triangularsec- This cut-out'assumes the form of:'an

the pin l3 as shown ingFigure "lwillpass through the flared slot II and into sary for a pressureto be exerted on the opposite pin in order to flex the opposite contact member back far enough to allow the first pin to move up through the triangular cut-out.

The possibility of too much pressure or improperly applied pressure being applied while rotating a lamp, either during the process of inserting or withdrawing it from its socket, and thereby causing one of the base pins to strike up against a side of the cut-out with such force that it will snap off a piece of the upper portion of the lamp socket, is not present in this type of'socket.

If one of the base pins were rotated too far either to the right or to the left, the other pin would slide along the base I4 of the triangular cut-out as soon as the first pin struck against the side of the cut-out. The feature in my invention that permits this correction of improper and excessive pressures in the rotation of the lamp is the fact that there is no fulcrum against which one of these pins could rest and thereby allow the excessive or improperly applied pressure to expand its force through the other pin and-against the side of the cut-out.

Due to the'fact that there is usually a small shoulder on the base pin at the point where the pin extends into the base, the sides of the triangular cut-out 8 are beveled, thereby providing a more rigid and positive seating of the lamp in the socket, The slot Ii is rounded as shown in Figures 1 and 2 in order to provide for an easier insertion of a base pin therethrough especially when the pins on the other end of the lamp have already passed down through the corresponding slot in the other socket.

When a lamp is to be removed from its sockets, there is no danger of twisting or straining the pins because the lamp may be rotated in either a clockwise or counter-clockwise direction. In either case, the pressure exerted in the rotation will cause one of the, spring contact fingers to flex and thereby release one of the base pins. This pin will then slide up along the adjacent side of the triangular cut-out 8' and assume theposition as shown in Figure 7, for example. 'When the lamp is rotated-sufficiently to bring pin I2 in alignment with slot II, the rotating motion may be stopped and the lamp withdrawn in an upward manner, the pin l3 sliding along side III while the lamp is being withdrawn. If the rotating motion is continued, no harm can be done to the lamp base or to the lamp socket, for no great amount of pressure will be able to be exerted through the pin l2 on the side ID of the triangular cut-out due to the absence of any fulcrum against which the pin I3 could rest.

The spring contact fingers 5 and 6 of a. contour substantially as shown in Figure 1 are seated in the base member in such a manner that they are kept from touching each other 'by the separating stud 1, and, in their lower extension, are flush with the restraining studs *3 and 4 which serve to increase the tension of the contact members againstythe base pins, thus assuring a firm and positive locking contact.

The lower extremity of the base member is dye cast in a manner as to provide a contour substantially as shown in Figures 1 and 3. .The contact members 5 and 6 may be bent at right angles at their lower extremities so as to form screw plates for; the screws l5 and I6. Lead-in wires may be connected to the contact fingers through the cut-outs I1 and I8, thereby establish ing an electrical contact.

The cover plate I is fastened to the base member 2-by means of screws or the like driven into the'studs 1 and I9 provided therefor'in the base member 2. I upper part of the cover plate projects through the triangular cut-out I of the base member 2 when the cover plate is attached in a flush mounting manner to the base member. This stud serves as a safety device in helpingelinnnate any possibility of shock from contact with the spring out.

- What I claim is:

fingers extending up through the' triangular cutl, A contact socket for a'lamp having twopin contacts, said socket comprising: a memberoi" insulating material having a flat surface with an opening therein bounded on the outside by an isosceles triangle whose apex meets an edge or said flat surface at a slot in said edge and on the inside by a small circle; and two'spring'contact fingers at opposite sides of said triangle and above the base of said triangle, thedistance between said fingers being less than the shortest" distance from a'base corner of the triangle to the opposite side.

2. A contact socket for a lamp having two'pin contacts, said socket comprising: a member of insulating material having a'flat surface with an opening therein bounded on the outside by an isosceles triangle whose apex meets an edge' of said flat surface at aslotixf'saidedgej and two spring contact fingers at opposite sides of 'said' triangle and above the base' of said triangle, the a distance between said fingers being less than the shortest distance from a base comer of thetriangle to the opposite side.

I HENRY J. McCAR'I'HY,

The stud 20 in the middle of the 

